Greenish-blue hexabromindigo.



UNITED PATENT OFFICE.

' No Drawing.

, indigo ma Amazons! sofimm'r-"annixann'irmsss, or iioons'r-on-rrm-mam,GERMANY, AS-

SIGNORS "IO I'ARBWER KE VORM. MEISTER,' LUCIUS & rmtmmo, orHooHsr-oN-rnn mnn, assass ns conroaa rron oronnmam'.

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To all whom it may concern:

Be it known that we, ALBRECHT-SCHMIDT Ph. D., and KARL Tnmss, Ph. D.,citizens o the Empire of Germany, residing at Hiichston-the MainGermany, have invented certain new and useful Improvements inGreenish-Blue Hexabromindigo, of which the following is a specification.

In the literature it is stated that by bromination of indigo or ofdibromindigo no higher brominated indigo can be obtained than thet'etrabromindigo (sec German Patent 195291). It is further stated that ahexnhalogenindigo d can only e obtained y treating withbronun andnitrobenzene the p-halogen derivatives of indigo which are onlyobtainable by synthesis and not by halogenation of indigo. \Ve have nowfound that not only is pentahalogenindi o obtainable from indigo, (asclaimed in S. patent a plicat-ion, Ser. No. 442,625, of July 8, 1908?,but that even hexahalo enindigoes can be produced, if the process 0bromination hereafter specified is employed, involving the use of a larer quantity of bromin than that em loye for the manufacture ofpentabromin igo, and preferably the use of an elevated temperature, heatapplied for a longer tperiod, and a more highly concentrated sul uricacid; in the place of the indigo also the brominated indigocs, such asmono-, di-, triand tetrabromindigo may be used, all of which, includingindigo itself, may be comprised under the term indigo substancesunsubstituted in para position to the CO group. This new hexabrominatcdindi o dyes in the vat very clear greenish lue tints. Therefore thisdyestutl is entirely different, in regard to its composition,constitution and properties, from t to hexahalogenmdigo g-p-dicilortetrabromindigo) described in ermn'n Patent No. 105291 andwhich is ob tained from the synthetically produced -pdichlorindigotbybromination in nitro enzene.

, The:- process of. making hexabrominated be carried out inthe'following manner: ndigo or brominated indigo prw duced byIbromination is-heated with an 'excess of. bromin for some. time ,to.about 100-120 C. under; pressure, or bromina'ted 4 indigo. obtainedbygbrommationfi is treated Specification of Letters Patent. Applicationfiled February 17, 1909. Serial No. 478,433.

eing reddish-blue tints Patented May 13, 1913.

with the quantity 'of bromin calculated for hexabromindigo, orpreferably with an excess of bromin, in a sulfur acid, which termimplies highly-concentrated sulfuric acid of for instance 98% strengthor monohydrate, or chlorosulfonic acid, or slightly uming sulfuric acidof for instance 98% strength, or in monohydrate, or in chlorosulfonicacid or in slightly fuming sulfuric acid, durin which operations thetemperatures employed may be the lower the more highly concentrated thesulfuric acid is, as will be seen by the following examples:

Example I: 26 parts by weight of indigo are slowly poure into 260 partsof well cooled bromm. The mass is then stirred for some time withoutcooling and is finally heated for several hours to about 120 C. underpressure. The excess of bromin may be removed by distilling it off or bymeans of a current of air or by washin with carbon tetrachlorid. Thereenishlack mass substantially consists o a erbromid of a hexabrominatedindigo. i or producing from it the hexabromindigo, the mass is pouredinto a bisulfite solution and ice, filtered off and washed with water.The hexabrominated indigo is thus obtained as a blue to rconish-blueowder'of the constitution (L, LO,N,Br,,, w liCil is insoluble in water,soluble in concentrated sulfuric acid with a blue color, and soluble incold anilin with a reenish-blue to dark-blue color. Its capabi ity ofdissolving in organic solvents, such for instance as anilin,nitrobcnzene. etc., is much greater than that of the tetrabromindi o.This hexabromindigo is also soluble in allialine hydrosulfite solutions,thereby producing a vat which dyes cotton pure greenish-blue tints ofremarkable brightness, as distinguished from the hexabromindigo describein German Patent No. 195,291 which dyes bright reddish-blue tints; inartificial light the dyeings obtainable by the herein-de- 0 2 Itishereby certified that in Letters Patent No. 1,061,781., granted, May13, 1913, upon the application of Albrecht Sehm idt and Karl Thiess,of'Hoehst-on-the-Maim I, J Germany, for an improvement in Greenish-BlueHexabromindigo, an error appears in the print-ed specification requiringcorrectionas follows: Page -1, lines I E 60 63 strike out the words offor instance 98% strength, or in monohyd rate, or

in chlorosulfonie acid or in slightly fuming sulfuric acid; and that thesaid L Y I I v g Letters Patent should be read with this correctiontherein that the same may .v i 4 conform to the record of the case inthe Patent Oflice.

g Signed and sealed this ith day of August, A. D., 1914. t:

g [sssn] L i- Q Q tion is finished by pouring the mass into a blsulfitesolution and 1ce,'filter1n, and dry ing it. The dyestufl shows similarproper-v ties to that obtained according to Example 1.

Example III: 42 parts by weight of dibromindigo are gradually introducedinto a well cooled mixture of (55-75 parts of bl'OlTllll and 420 partsof fuming sulfuric acid containing about 2-57v of anhydrid; the mass isstirred for a short time while further cooling and afterward withoutcooling and heated during several hours to i i-52 C. The working, up isconducted in the same manner as stated in Example II; The dyestufi'showssimilar properties to that obtained according to Example I.

In general, it is sufiicicnt and necessary that indigo, or itshromsubstitution prod- .ucts obtained hybrominating indigo, be

treated, preferably while heating, with an excess of bromin of at leastone atom of bromln above that quantity of brominwhich Copies of thispatent may be ohtaincd for is 'tl'ieoretically required tor thehex-abalobed our invention what furic, acid with a blue; colore and. incold anilin with a greenish hluef" to dark-blue color, yieldingbyoxidation wit-h-nitrio' acid iinpresenceof glacial acetic a f a4.5.7-tribromisatin', melting at 257? (3., lso soluble in alkalinehydrosulfite 'solution"'-v forming thcn a vat whichdyeS COtton puregreenish- .bluetmtsJ i In testimony whereof, we afiix our signatures inpresence of'two witnesses. ALBRECHT SCHMIDT.

KARL THIESS.' lVitnesses CARL GRUND, JEAN GRUND.

five centseach, hy-addrcssingthe Commissioner of Patent Washington. D.C.

.J.f T. NEWTON,

Acting Commissioner of Patents.

0 2 It ishereby certified that in Letters Patent No. 1,061,781.,granted, May 13, 1913, upon the application of Albrecht Sehm idt andKarl Thiess, of'Hoehst-on-the-Maim I, J Germany, for an improvement inGreenish-Blue Hexabromindigo, an error appears in the print-edspecification requiring correctionas follows: Page -1, lines I E 60 63strike out the words of for instance 98% strength, or in monohyd rate,or

in chlorosulfonie acid or in slightly fuming sulfuric acid; and that thesaid L Y I I v g Letters Patent should be read with this correctiontherein that the same may .v i 4 conform to the record of the case inthe Patent Oflice.

g Signed and sealed this ith day of August, A. D., 1914. t:

g [sssn] L i- Q Q tion is finished by pouring the mass into a blsulfitesolution and 1ce,'filter1n, and dry ing it. The dyestufl shows similarproper-v ties to that obtained according to Example 1.

Example III: 42 parts by weight of dibromindigo are gradually introducedinto a well cooled mixture of (55-75 parts of bl'OlTllll and 420 partsof fuming sulfuric acid containing about 2-57v of anhydrid; the mass isstirred for a short time while further cooling and afterward withoutcooling and heated during several hours to i i-52 C. The working, up isconducted in the same manner as stated in Example II; The dyestufi'showssimilar properties to that obtained according to Example I.

In general, it is sufiicicnt and necessary that indigo, or itshromsubstitution prod- .ucts obtained hybrominating indigo, be

treated, preferably while heating, with an excess of bromin of at leastone atom of bromln above that quantity of brominwhich Copies of thispatent may be ohtaincd for is 'tl'ieoretically required tor thehex-abalobed our invention what furic, acid with a blue; colore and. incold anilin with a greenish hluef" to dark-blue color, yieldingbyoxidation wit-h-nitrio' acid iinpresenceof glacial acetic a f a4.5.7-tribromisatin', melting at 257? (3., lso soluble in alkalinehydrosulfite 'solution"'-v forming thcn a vat whichdyeS COtton puregreenish- .bluetmtsJ i In testimony whereof, we afiix our signatures inpresence of'two witnesses. ALBRECHT SCHMIDT.

KARL THIESS.' lVitnesses CARL GRUND, JEAN GRUND.

five centseach, hy-addrcssingthe Commissioner of Patent Washington. D.C.

.J.f T. NEWTON,

Acting Commissioner of Patents.

